Power Plant Engineering(Mechanical Engineering ) Questions and answers for exam Preparation

Question 1. The following present serious difficulty in designing reactor shield

Alpha particles
Beta particles
Thermal neutrons
Fast neutrons and gamma rays

Explanation:-

Answer: Option D. -> Fast neutrons and gamma rays
Fast neutrons and gamma rays presance are serious difficulty in designing reactor shield

Question 2. The most commonly used moderator in nuclear plants is

Heavy water
Concrete and bricks
Graphite and concrete
Graphite

Explanation:-

Answer: Option D. -> Graphite
Graphite is the most commonly used moderator in nuclear plants

Question 3. Breeder reactor has a conversion ratio of

Unity
More than unity
Less than unity
Zero

Explanation:-

Answer: Option B. -> More than unity
In a breeder reactor, the conversion ratio is higher than 1. "Break-even" is achieved when the conversion ratio reaches 1.0 and the reactor produces as much fissile material as it uses

Question 4. Uranium has isotopes

U234
U235
U238
All of these

Explanation:-

Answer: Option D. -> All of these
Uranium has isotopes
U234
U235
U238

Question 5. Hydrogen is preferred as better coolant in comparison to CO2 because former

Is lighter
Is inert
Has high specific heat
Is a good conductor

Explanation:-

Answer: Option C. -> Has high specific heat
Hydrogen is preferred as better coolant in comparison to CO2 because former has high specific heat.

Question 6. Which of the following type of pump is used in liquid metal cooled reactor for circulation of liquid metal

Centrifugal
Axial
Reciprocation
Electromagnetic

Explanation:-

Answer: Option D. -> Electromagnetic
Electromagnetic type of pump is used in liquid metal cooled reactor for circulation of liquid metal

Question 7. A nuclear unit becoming critical means

It is generating power to rated capacity
It is capable of generating much more than rated capacity
There is danger of nuclear spread
Chain reaction that causes automatic splitting of the fuel nuclei has been established

Explanation:-

Answer: Option D. -> Chain reaction that causes automatic splitting of the fuel nuclei has been established
A nuclear unit becoming critical means Chain reaction that causes automatic splitting of the fuel nuclei has been established
when the reactor is in a configuration such that one neutron from each atom fissioned causes another fission and then the reactor is said to be critical

Question 8. U238 will undergo fission by

High energy (fast) neutrons alone
Low energy (slow) neutrons alone
Either fast or slow neutrons
Medium energy neutrons

Explanation:-

Answer: Option A. -> High energy (fast) neutrons alone
U238 will undergo fission by high energy (fast) neutrons alone.
The much more abundant uranium-238 does not undergo fission and therefore cannot be used as a fuel for nuclear reactors. However, if uranium-238 is bombarded with neutrons it absorbs a neutron and is transformed into uranium-239.

Question 9. Artificial radioactive isotopes find application in

Power generation
Nucleonic devices
Nuclear fission
Medical field

Explanation:-

Answer: Option D. -> Medical field
Artificial radioactive isotopes are formed when an atom is bombed with an accelerator or exposing it to slow moving neutrons in a nuclear reactor.
Artificial radioactive isotopes find application in Medical field

Question 10. U235 will undergo fission by

High energy (fast) neutrons alone
Low energy (slow) neutrons alone
Either fast or slow neutrons
Medium energy neutrons

Explanation:-

Answer: Option C. -> Either fast or slow neutrons
U235 will undergo fission by either fast or slow neutrons.
For fission of uranium-235, the predominant radioactive fission products include isotopes of iodine, caesium, strontium, xenon and barium.